Meanwhile, Yemen’s interior ministry said in an overnight statement that the coast guard was on alert in several provinces following information that “terrorist groups belonging to Somalia’s (Al-Qaeda-affiliated) Shebab are planning to enter Yemen to carry out terrorist attacks”.

The ministry ordered “increased deployment in security patrols along Yemen’s coast in coordination with naval forces... to arrest any elements and foil any suspected movement”.

It was unclear if the warning was linked to the attack in Lahij.

Tens of thousands of Somali refugees cross the Gulf of Aden every year to reach Yemen.